PARTICLE-CONTAINING MEMBRANE AND PARTICULATE ELECTRODE FOR ANALYTE SENSORS

• US 20100076283A1
• Filed: 09/17/2009
• Published: 03/25/2010
• Est. Priority Date: 09/19/2008
• Status: Active Grant

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Simpson, Peter C., Shults, Mark, Wightlin, Matthew, Boock, Robert J.
• Granted Patent: US 8,560,039 B2
• Time in Patent Office: Days
• US Class Current: 600/345
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/6848 Needles

Abstract

Systems and methods of use involving sensors having a particle-containing domain are provided for continuous analyte measurement in a host. In some embodiments, a continuous analyte measurement system is configured to be wholly, transcutaneously, intravascularly or extracorporeally implanted.

Claims

1. An analyte detection system for continuous in vivo detection of an analyte, the system comprising:

a continuous analyte sensor comprising a working electrode configured for implantation in a host, wherein the working electrode comprises an electroactive surface, the continuous analyte sensor further comprising a membrane located over the working electrode, wherein the membrane comprises an enzyme domain and a particle-containing domain, wherein the particle-containing domain comprises a conductive component dispersed in a non-conductive component, wherein the conductive component comprises a plurality of conductive particles, wherein the particle-containing domain is located more distal to the electroactive surface than the enzyme domain, and wherein the particle-containing domain is configured to electrochemically react with at least one interfering species; and

sensor electronics configured to generate a signal associated with an analyte in the host.

2. The system of claim 1, wherein the conductive component comprises at least one material selected from the group consisting of platinum, platinum-iridium, iridium, palladium, graphite, gold, silver, silver chloride, carbon, and conductive polymers.

3. The system of claim 1, wherein particles comprise from about 10 wt. % to about 40 wt. % of the particle-containing domain.

4. The system of claim 1, wherein the non-conductive component comprises a polymer.

5. The system of claim 4, wherein the polymer comprises an analyte-permeable polymer.

6. The system of claim 5, wherein the analyte-permeable polymer comprises a hydrophilic polymer.

7. The system of claim 5, wherein the analyte-permeable polymer comprises at least one of polyurethane or silicone.

8. The system of claim 1, wherein the sensor electronics are configured to apply a potential to the particle-containing domain.

9. A sensor system for measurement of a species in a host, the sensor system comprising:

an electrode configured for implantation in a host, the electrode comprising an electroactive surface;

a membrane disposed over the electrode, the membrane comprising a particle-containing domain, wherein the particle-containing domain comprises a sensor element configured to measure a concentration of a species; and

sensor electronics configured to generate a signal associated with a concentration of the species in the host.

10. The sensor system of claim 9, wherein the membrane further comprises an enzyme-containing domain located adjacent to the particle-containing domain.

11. The sensor system of claim 9, wherein the membrane further comprises an oxygen permeable domain located between the electroactive surface and the particle-containing domain.

12. The sensor system of claim 9, wherein the electroactive surface is configured for generating oxygen.

13. The sensor system of claim 9, wherein the particle-containing domain is a first sensor element configured to measure a concentration of a first species, and wherein the electrode is a second sensor element configured to measure a concentration of a second species.

14. The sensor system of claim 13, wherein the first species and the second species each comprise at least one of an analyte or a drug.

15. The sensor system of claim 13, wherein the particle-containing domain substantially reduces flow therethrough of at least one of the first species or the second species.

16. The sensor system of claim 13, wherein the sensor electronics are configured to apply a first bias potential to the first sensor element and to apply a second bias potential to the second sensor element, and wherein the first bias potential and the second bias potential are different.

17. A method for detecting a signal associated with an analyte, the method comprising:

providing a continuous analyte sensor configured for implantation into a tissue of a host, the continuous analyte sensor comprising a working electrode and a membrane located over the working electrode, wherein the membrane comprises an enzyme domain and a particle-containing domain, wherein the particle-containing domain is located more distal to the working electrode than the enzyme domain;

electrochemically reacting the particle-containing domain with at least one interfering species; and

detecting a signal from the continuous analyte sensor, wherein the signal is indicative of a concentration of an analyte.

18. The method of claim 17, wherein the continuous analyte sensor is configured to contact a biological sample.

19. The method of claim 17, wherein the membrane is configured to allow the analyte to diffuse therethrough.

20. The method of claim 17, wherein electrochemically reacting comprises applying a potential to the particle-containing domain.